title: Minimally invasive compared with open lumbar laminotomy: no functional benefits at 6 or 24 months after surgery.
abstract: BACKGROUND
  Comparative studies between open and minimally invasive surgical (MIS) approaches for the treatment of spinal stenosis have mainly investigated immediate postoperative parameters.
  
  
  OBJECTIVE
  We aimed to compare the postoperative improvements in functional and pain scores between open versus MIS lumbar laminotomy and to describe the complications of each method.
  
  
  METHODS
  We conducted as retrospective review of prospectively collected data.
  
  
  METHODS
  We included 113 patients.
  
  
  METHODS
  Visual analog scale for back and leg pain, Oswestry Disability Index (ODI), the North American Spine Society score on neurogenic symptoms (NS), and average Short Form Health Survey-36 (SF-36) score. Accidental durotomies and patients with reoperations are presented.
  
  
  METHODS
  We obtained a list of patients who underwent either MIS or open unilateral one-level lumbar laminotomy for the treatment of neural foraminal or lateral recess stenosis with unilateral leg NS. Outcome measures are presented at 6 and 24 months postoperatively.
  
  
  RESULTS
  From 2000 to 2008, 113 patients (30 open, 83 MIS) underwent a one-level lumbar laminotomy and had complete postoperative data available for analysis. Between the approaches, there were no differences in baseline demographic data or functional scores. At 6 and 24 months after surgery, there were no differences in improvement in back or leg pain, or improvement in ODI, NS, or SF-36 scores. The MIS group reported greater satisfaction with treatment at 6 months (p=.009) but not at 24 months. Within the MIS group, three patients (3.6%) experienced an inadvertent durotomy and two patients (2.4%) underwent fusion of the operated segment within 24 months.
  
  
  CONCLUSIONS
  Compared with an open approach, MIS lumbar laminotomy gave no clear advantages in longer term functional or pain scores. The MIS group also had patients with inadvertent durotomies and reoperation within 2 years. In any lumbar decompressive surgery, the purported advantages of an MIS approach should be carefully weighed against potential complications. For a relatively simple surgery such as laminotomy, the open approach remains a safe and straightforward option.
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, 20 College Rd, Level 4, Singapore 169856, Singapore. Electronic address: med80199@yahoo.com.
authors.forename: Chia-Liang
authors.initials: CL
authors.lastname: Ang
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, 20 College Rd, Level 4, Singapore 169856, Singapore.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Phak-Boon Tow
authors.affiliation: Department of Clinical Research, Singapore General Hospital, 20 College Rd, Level 4, Singapore 169856, Singapore.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Fook
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, 20 College Rd, Level 4, Singapore 169856, Singapore.
authors.forename: Chang-Ming
authors.initials: CM
authors.lastname: Guo
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, 20 College Rd, Level 4, Singapore 169856, Singapore.
authors.forename: John Li-Tat
authors.initials: JL
authors.lastname: Chen
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, 20 College Rd, Level 4, Singapore 169856, Singapore.
authors.forename: Wai-Mun
authors.initials: WM
authors.lastname: Yue
authors.affiliation: Department of Orthopaedic Surgery, Singapore General Hospital, 20 College Rd, Level 4, Singapore 169856, Singapore.
authors.forename: Seang-Beng
authors.initials: SB
authors.lastname: Tan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007796:Laminectomy / Q000379:methods*; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000175:diagnosis; D012086:Reoperation; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000379:methods*; D013130:Spinal Stenosis / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult
keywords: Laminectomy; Minimally invasive surgical procedures; Reoperation; Spinal stenosis; Visual analog pain scale